var aneObj = function(){
	//start point,control point,end point(sin)
	this.rootx = [];
	this.headx = [];
	this.heady = [];
	this.amp = [];
	this.angle = 0;
}
aneObj.prototype.num = 50;
aneObj.prototype.init = function(){
	for (var i = 0; i < this.num; i++) {
		this.rootx[i] = i*16+Math.random()*20;//间距	16
		this.headx[i] = this.rootx[i];
		this.heady[i] = canHeight - 250+Math.random()*50;
		this.amp[i] = Math.random()*50+50;
	}
}
aneObj.prototype.draw = function(){
	this.angle += deltaTime * 0.0008;
	var l = Math.sin(this.angle);//[-1,1]
	ctx2.save();
	ctx2.globalAlpha = 0.6;
	ctx2.lineWidth = 20;
	ctx2.lineCap = "round";
	ctx2.strokeStyle="#3b154e";	
	for (var i = 0; i < this.num; i++) {
		ctx2.beginPath();
		ctx2.moveTo(this.rootx[i],canHeight);
		this.headx[i] = this.rootx[i]+l*this.amp[i];
		ctx2.quadraticCurveTo(this.rootx[i],canHeight-100,this.headx[i],this.heady[i]);
		ctx2.stroke();
	}
	ctx2.restore();
}